Optimization and Implementation of the Virus Extraction Method for Hepatitis E Virus Detection from Raw Pork Liver

AbstractHepatitis E virus (HEV) has been frequently detected from pork liver and liver products, which can usually cause self-limiting diseases in healthy adults, yet may result in fatality in immunosuppressed groups. Nevertheless, there is so far no standardized method for HEV detection available from pork liver and/or liver products. The present study aimed to optimize the virus extraction method of HEV from raw pork liver, which is often consumed in Asia undercooked to avoid a grainy texture. By comparing different sample preparation protocols and by applying the selected protocol to 60 samples collected from Singapore retail markets, we demonstrated that homogenization of 0.25  g raw pork liver with FastPrep™ Lysing Matrix Y containing yttria-stabilized zircondium oxide beads in 2 ml tubes and with harsh mechanical force at 6 ms−1, 40  s/cycle, for 5 cycles with 300 s pause time after each cycle is promising in both releasing the potentially intracellular viruses and resulting in satisfactory virus recovery rates (>  1%). A high prevalence (52%) of HEV genome was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) from the 60 samples collected from Singapore retail markets imported from Indonesia, Australia and Malaysia. However, RNase treatment decreased the HEV prevalence to 3 3.3%, and all of the 20 positive samples were with high RT-qPCR Ct values above 35, suggesting that the positive RT-qPCR signals maybe largely due to t...
Source: Food and Environmental Virology - Category: Virology Source Type: research